In an Experimental Test of the Effects of Vitamin B-12

question 47

Multiple Choice

In an experimental test of the effects of Vitamin B-12 on problem-solving performance, ______ is the independent variable, and ______ is the dependent variable.

• A) problem-solving performance; the vitamin
• B) problem-solving performance; a placebo
• C) the vitamin; problem-solving performance
• D) a placebo; the vitamin

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Definitions:

Gallbladder

A small, pear-shaped organ located beneath the liver, which stores and concentrates bile, a digestive enzyme produced by the liver.

Salivary Glands

Glands located in the mouth that produce saliva, which begins the process of digestion and keeps the mouth and other parts of the digestive system moist.

Mouth

The opening in an organism's body that usually begins the digestive tract, where food is ingested.

Pharynx

A muscular tube that connects the mouth and nasal passages with the esophagus and larynx, serving both the respiratory and digestive systems.